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Problem with SSH key-based authentication




I have successfully added a new Linux device, configured SSH with public key authentication, and added a few SSH-based sensors (meminfo, load average, etc).

The sensors were responding successfully but then for operational reasons I need to change the login/key used for SSH authentication to a different account.

I changed the SSH configuration on the device to use the new user/private key but no matter what I try I keep getting "Authentication Failed" error from the sensors. Tried restarting PRTG Core without success.

The Linux server being monitored is reporting "Failed publickey for <loginname>" in its auth log everytime PRTG attempts to connect.

I can successfully connect to the server using the new account via a separate SSH client configured for RSA authentication with the same exact key used in PRTG so at this point I am really stumped as to what the issue could be.

We are running PRTG Linux server is configured with OpenSSH and SSH2 is used

Any thorughts?

Thank you


key prtg ssh

Created on Dec 12, 2011 9:02:36 PM

4 Replies



Dear Frank,

this is unfortunately a known issue, PRTG uses the first key "for ever", we are investigating this. Please bear with us.

best regards.

Created on Dec 13, 2011 2:25:39 PM by  Torsten Lindner [Paessler Support]



Thanks for the quick reply. Glad to know its not us (I was starting to pull my hair out on this one :) )

Created on Dec 13, 2011 6:05:48 PM



has this been resolved yet?

Created on Oct 16, 2012 10:05:47 PM



This issue here from PRTG 9.1.5 is resolved yes, we're now on version PRTG 12.3.4

Created on Oct 17, 2012 3:23:49 PM by  Torsten Lindner [Paessler Support]

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